Method and apparatus for making foam/concrete building panels

ABSTRACT

A continuous process is used to make concrete building products with an expanded polystyrene core. The expanded polystyrene is fed into the inlet of an elongated guiding channel which has a longitudinally split mold. The expanded polystyrene is guided along the guiding channel without any means for pulling the expanded polystyrene. Concrete is then pumped into the split mold first through an first aperture in a first mold section of the split mold and then through another aperture, in a second mold section of the split mold, so that the concrete is coated on at least two opposing sides of the expanded polystyrene.

This is a non provisional of 60/033,150 filed Dec. 13, 1996.

FIELD OF THE INVENTION

The present invention relates to a continuous process for makingbuilding products by coating an expanded polymeric form with a facingmaterial, preferably concrete, stucco or plaster.

BACKGROUND TO THE INVENTION

Structural building blocks and non-structural mouldings made with a foamcore and a concrete or plaster coating, are known. An example of such astructural building block with a concrete coating is shown in U.S. Pat.No. 4,774,794 to D. J. Grieb which issued Oct. 4, 1988. Generally,structural building blocks, made with a foam core and a concretecoating, allow interconnection with other blocks to produce a flat,two-sided panel for use in forming walls, floors, ceilings and relatedstructures. It is preferable that the foam core be exposed on the edgeswhere the panels interconnect so that there is a continuous core ofinsulating material. The building blocks tend to be impervious tohumidity and water and resist cracking, rotting, weathering, fading andhave other advantages

It is also known to make blocks, panels and mouldings with a foam coreand a concrete exterior using either a batch process, or a continuousprocess. For example, a pultrusion process is known in which a preformedfoam core slab is pulled through a pultrusion mandrel by a roller chainwith caterpillar gripping pads. Concrete mixtures are then fed into thepultrusion mandrel on both sides of the foam core slab. After sufficientcuring of the concrete, the foam core block so formed can be cut with atravelling carbide tipped cut-off saw. One of the difficulties of thisprocess is that there are significant problems caused by fouling of thechain with concrete, because of leakage of concrete onto and between thegripping pads and onto the chain and related surfaces. In addition,setting up the pultrusion mandrel is extremely time consuming andadditional processing is required to remove excess foam material. Animproved process is highly desirable and the present invention isdirected to providing such an improvement.

It is proposed to make such building blocks with an alternativecontinuous process. Surprisingly, it has been found that it is possibleto make such building panels without the need to pull the foam corethrough the process.

SUMMARY OF THE INVENTION

The present invention provides a continuous process, with upstream anddownstream longitudinal directions, for making an elongated coatedbuilding product comprising a longitudinal expanded synthetic polymericform having a desired cross-sectional shape, and having a longitudinallycontinuous coating of a facing material on at least a portion of aperiphery of the cross-sectional shape, said process comprising:

a) feeding the expanded synthetic polymeric form longitudinally into theinlet of an elongated guiding channel which comprises a longitudinallysplit mould having an internal cross-sectional shape suitable to producea desired external cross-sectional shape of the coated building product;

b) guiding the expanded synthetic polymeric form along the guidingchannel, without any means for pulling the expanded synthetic polymericform after the expanded synthetic polymeric form enters the inlet of theguiding channel;

c) feeding the facing material into the split mould through a firstaperture in a first mould section of the split mould.

In an embodiment, the facing material is selected from the groupconsisting of concrete, gypsum, plaster. The concrete, gypsum or plastermay contain strengthening materials, e.g. glass fibre, cellulosic fibre.

In one embodiment, the split mould is a two-part split mould and thefacing material is additionally fed through a second aperture in asecond mould section of the split mould, so that the facing material iscoated on at least two opposing sides of the expanded syntheticpolymeric form.

In another embodiment, facing material is prevented from escapingupstream towards the inlet by sealing means between the split mould andthe expanded synthetic polymeric form.

In a further embodiment, the coated building product is a moulding stripwith at least one exposed face of the expanded synthetic polymeric form,in which process the exposed face is in sliding contact with a secondmould section of a two-part split mould which has no apertures thereinfor introduction of facing material.

In another embodiment, the building product is a moulding strip and thefacing material is plaster.

In yet another embodiment the expanded synthetic polymeric form is madefrom expanded polystyrene, polyurethane, phenolic or polyisocyanurate.

In a further embodiment, the building product is a building panel whichis coated on at least two sides with concrete, in which process theexpanded form is guided between first and second mould sections of atwo-part split mould, concrete facing material is fed through a firstaperture in the first mould section and through a second aperture in thesecond mould section.

In yet another embodiment, the building product is a building panelwhich is coated on at least two sides with the facing material and tiesare inserted transversely, at longitudinally spaced intervals, throughthe expanded form prior to feeding the expanded synthetic polymeric formlongitudinally into the inlet of the elongated guiding channel, suchthat when the expanded form is coated with the facing material, opposingcoatings of facing material are tied together by the ties.

In another embodiment, the expanded form and the facing material aremechanically locked by means of mating shapes of contracting faces ofthe facing material and the expanded form. Preferably the mating shapeis in the form of a dovetail joint.

In another embodiment, the process for making the building panelcomprises:

(a) feeding the expanded synthetic polymeric form longitudinally intothe inlet of the guiding channel and first and second mould sections ofa two-part split mould are slidingly sealed against at least one ofupper and lower portions of the expanded form;

(b) feeding facing material, selected from the group consisting ofconcrete and gypsum, into the split mould through the first aperture inthe first mould section and through the second aperture in the secondmould section.

In one embodiment, the second aperture is downstream of said firstaperture and there are sealing strips between the expanded syntheticpolymeric form and the first and second mould sections, at positionsslightly upstream of the first and second apertures.

In another embodiment, there is a back pressure plate between the secondmould section and the expanded synthetic polymeric form between theinlet of the guiding channel and the sealing strip which is upstream ofthe second aperture.

In a further embodiment, the polymeric expanded material is continuouslyprovided from an extrusion or fusion machine upstream of the inlet tothe guiding channel.

The present invention also provides an apparatus for a continuousprocess, with longitudinal upstream and downstream directions, formaking an elongated coated building product comprising a longitudinalexpanded synthetic polymeric form, said apparatus comprising:

a) an elongated guiding channel which has a longitudinally split mouldhaving an internal cross-sectional shape suitable to produce a desiredexternal cross-sectional shape of the coated building product, saidguiding channel having an inlet and an outlet;

b) means for guiding the expanded synthetic polymeric form along theguiding channel, without any means for pulling the expanded syntheticpolymeric form after the expanded synthetic polymeric form enters theinlet of the guiding channel;

c) means for feeding facing material into the split mould through afirst aperture in a first mould section of the split mould; and

d) sealing means in the guiding channel to prevent facing materialescaping upstream between the expanded synthetic polymeric form andmould sections, towards the inlet of the guiding channel.

In one embodiment, there is means for feeding facing material into thesplit mould through a second aperture in a second mould section of thesplit mould.

In another embodiment, the second aperture is downstream of said firstaperture and there is a sealing strip between the polymeric expandedmaterial and the second mould section at a position slightly upstream ofthe second aperture.

In a further embodiment, an extrusion or fusion machine for continuouslymaking polymeric expanded material is provided upstream of the inlet tothe guiding channel, for feeding polymeric expanded material into theinlet of the guiding channel.

In yet another embodiment, there is means for inserting tiestransversely through the expanded form, at longitudinally spacedintervals, between the extrusion or fusion machine and the inlet to theguiding channel, such that ends of the ties will protrude into thefacing material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cut-away section of a building panel made using a process ofthe present invention.

FIG. 2 is a schematic representation of apparatus used in the presentinvention.

FIG. 3 is a cross-sectional view of a plan of FIG. 2 through the planeindicated by X—X in FIG. 2.

FIG. 4 is a cross-sectional view of a split mould, and a building panelin a guiding channel of the present invention.

FIG. 5 is a cross-sectional view of another split mould and a buildingpanel in a guiding channel of the present invention.

FIG. 6, which is after FIG. 1, is a cross-sectional view of a splitmould, and a moulding strip in another guiding channel of the presentinvention.

FIG. 7 is a cross-sectional view of building panel of the presentinvention with a dovetail joint between the facing material and theexpanded form, and a transverse tie.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention is useful for making building panels with and anexpanded polymeric form, coated with a facing material. The preferredembodiments will generally be described hereinafter with reference toconcrete, but it is to be understood that other facing materials may beused, e.g. plaster, gypsum.

A cross-section of a building panel made in accordance with the presentinvention is shown in FIG. 1. The building panel 10 comprises anexpanded synthetic polymeric form 13 sandwiched between layers of afacing material, e.g. concrete 12 and 13. In the embodiment shown, thelongitudinal edges 16 and 18 of the expanded form 13 are exposed. Thelongitudinal edges of building panel 10 are made so that they will matewith adjacent corresponding building panels. In the embodiment shown,one longitudinal edge has a longitudinal tenon 14 and the otherlongitudinal edge has a longitudinal mortise 15. In order to ensurecontinuity of expanded synthetic polymeric form 13 between adjacentpanels, it is preferable that the expanded synthetic polymeric form 13,at longitudinal edge 18 is proud of the bottom 17 of mortise 15. Thisprovides spacing for adhesive material between adjacent panels in orderto provide a tight joint. There may be control joint grooves 19.Typically, the expanded synthetic polymeric form is made of expandedpolyurethane, polystyrene, phenolic or polyisocyanurate. When thesynthetic polymer is foamed, e.g. foamed polyurethane, it is preferablethat the foams are so-called closed-cell foams in order to providegreater impermeability to vapours and liquids. Expanded polystyrene is apreferred material for the expanded form and is usually made with afusion process. The expanded form may have materials added to thepolymer, e.g. recycled carpet fibre. For building panels the layers 12and 13 typically are cementitious and typically comprise PortlandCement, sand, gravel and water and may include other additives known inthe art. For example, strengthening materials such as glass fibre rovingmay be added. Other materials may be added to improve chemicalstability, water-resistance, fire proofing or to colour the cement, e.g.latex, gypsum, pigments. As indicated above, other building panels maybe made with facing material of gypsum, plaster of Paris and the like.Such materials may also include strengthening or other materials such asglass fibre, cellulosic fibre, pigments.

The building panel 10 may be made by a process which is illustrated inFIGS. 2 and 3. The expanded form 55 may be prepared in an expanded formmanufacturing and transport section 48 and delivered to a buildingmaterial forming section 40. FIGS. 2 and 3 show a continuous extrusionor fusion machine 49 which forms an expanded form 55 in a shape asrequired for the finished building panel, e.g. in the shape shown asform 13 in FIG. 1. The expanded form 55 is then guided by continuousconveyors 50 into a guiding channel 58 of building panel forming section40. The guiding channel 58 comprises two cooperating longitudinal mouldsections 41 and 42 of a split mould. The cross-sectional shape of theguiding channel 58 is made to conform to the exterior cross-sectionalshape of the required building panel 10.

As expanded form 55 enters the inlet to forming section 40 it passesbetween a back plate 53 and sealing sleeve 54. Back plate 53 is betweenmould section 42 and expanded form 55 and extends between the inlet ofguiding channel 58 and sealing sleeve 59. Sealing sleeve 54 is justupstream of concrete inlet 60 in mould section 41 and sealing sleeve 59is just upstream of concrete inlet 61.

A short distance from the inlet of the guiding channel 58 there is aconcrete pump 45 or similar which is adapted to pump concrete into oneside of the guiding channel 58 through inlet 60 in mould section 41. Thesize of inlets 60 and 61 will depend in part on the consistency of thefacing material, e.g. concrete, and the pumping capacity of the pumps 45and 46. For example, inlet 60 may extend substantially from the top tothe bottom of the mould 41 or may be narrower, e.g. be a large diameterpipe. A similar concrete pump 46 is situated on the opposing side of theguiding channel 58, preferably at a location downstream of the locationof concrete pump 45. This is a preferred arrangement, but concrete pump46 may be directly opposite to concrete pump 45. Preferably, thedistance between concrete pumps 45 and 46 is from 15 to 45 cm.

It will be understood that mould sections 41 and 42 should be adequatelysupported so that they do not bow or deform vertically of horizontallyunder the weight of the continuously forming building panel or under thepressure from the concrete being extruded into guiding channel 58.Typically, the mould sections 41 and 42 are made of polyurethane and aresupported by beams of steel or aluminum. Preferably the mould sections41 and 42 are lined, upstream of inlet apertures 60 and 61 with amaterial of low coefficient of friction, e.g. aluminum, steel, highdensity polyethylene, ultra high molecular weight polyethylene or afluoropolymer such as polytetrafluoroethylene (e.g. Teflon®). Thesealing sleeves 59 and 54 are typically of a low friction polymericmaterial, e.g. high density polyethylene, aluminum or steel. There maybe apertures 47 in the sides of mould sections 41 and 42, downstream ofconcrete pumps 45 and 46. Typically for concrete, apertures 47 are from12-20 mm in diameter, depending on the consistency of the concretemixer. Other sizes may be more appropriate for plaster, gypsum or otherfacing materials.

The process for making a building panel is illustrated further byreference to FIG. 4. The guiding channel comprises a longitudinallysplit mould, which consists of first longitudinal mould section 41 andsecond longitudinal mould section 42. First mould section 41 has a mainwall 70, an upper wall 71 and a lower wall 72. Upper wall 71 has acontrol joint ridge 73 which corresponds to a control joint groove inconcrete layer 75 of the building panel. Lower wall 72 has a similarcontrol joint ridge 74. Main wall 70 is supported and prevented frombowing outwardly by steel beam 76. Second mould section 42 has a similarmain wall 77, upper wall 78, lower wall 79 and control joint ridges 80and 81, and is supported by steel beam 82. First mould section 41 has arelief vent 100. Second mould section 42 also has a vent but is notshown as, in this embodiment, it is downstream of relief vent 100.

Upper walls 71 and 78 have sealing lips 83 and 84 respectively, andlower walls 72 and 79 have sealing lips 85 and 86 respectively. Sealinglips 83 and 84, and sealing lips 85 and 86 are spaced apart sufficientlyto provide sliding seals with tongues 87 and 88 of expanded form 89. Thespacing is effected by clamps which are not shown.

Mould section 42 and beam 82 have a concrete inlet 90 into whichconcrete may be fed.

In the embodiment shown in FIG. 4, expanded form 89 has threelongitudinal internal cavities 91, 92, 93, four longitudinal externalgrooves 94-97, and two external corner grooves 98 and 99. It will beunderstood that the number and shape of any internal cavities andexternal grooves may be changed to suit the particular building product.For example there may be a single internal cavity or many internalcavities; they may be square, rectangular, circular or any other shapein cross-section. Similarly, the number and shape of any externalgrooves may be changed to suit the particular building product. Forexample, the grooves may be semi-circular, triangular, rectangular incross-sectional shape and they may be on one side of a building panel orboth sides, depending upon the purpose to which the panel is to be put.

In the process of making the building panel shown in FIG. 4, expandedform 89 is pushed into the guiding channel so that tongue 87 isslidingly guided between sealing lips 83 and 84, and tongue 88 isslidingly guided between sealing lips 85 and 86. Mandrels 101, 102 and103, in cavities 91, 92 and 93 respectively also assist in guidingexpanded form 89. Mandrels 101, 102 and 103 also function to preventcrushing of the expanded material into cavities 91, 92 and 93 as aresult of pressure exerted on expanded form 89 when concrete is pumpedinto the cavities between expanded form 89 and mould sections 41 and 42.Mandrels 101, 102 and 103 extend from the extrusion or fusion machine(not shown) to a position just downstream of the second concrete pump(not shown).

As the-expanded form 89 is pushed into the inlet of the guiding channel,so are steel rods 104 and 105. They are guided so that they are situatedin the spaces formed by longitudinal corner grooves 98 and 99respectively. Steel rods 104 and 105 provide additional strength to thebuilding panel, and are generally only required for load-bearingbuilding panels such as for roofs.

Concrete 75 is first pumped into the cavity between mould section 41 andexpanded form 89. Concrete 106 is then pumped through an aperture 90(the extent of which is delineated by walls 90 a) into the cavitybetween mould section 42 and expanded form 89. Excess pressure may berelieved through vent 100. Concrete 106 also moves into longitudinalgrooves 94-97 to provide better bonding between concrete 105 andexpanded form 89, and to assist in preventing problems associated withslumping of the concrete and structural strength benefits. Such groovesmay be cut into the expanded form immediately after extrusion or theexpanded form may be extruded with the grooves.

Any suitable extrusion or fusion machine 49 may be used in the presentprocess. Although the apparatus has been described above with anexpanded polymer formation and conveying section, the formation of theexpanded form material can be made at a separate location and theexpanded form 55 be fed in by other means, e.g. a conveyor or ahydraulic ram.

When the expanded synthetic polymeric form 89 has tongues 87 and 88, atleast one of the tongues e.g. 88 may need to be trimmed after theconcrete layers have been added. This can be done relatively easily byhot wire cutting of the tongue. Preferably, however, the expandedsynthetic polymeric form is made so that no post-trimming is necessary.A suitable split mould for processing such expanded synthetic polymericform is shown in FIG. 5. It will be understood that other arrangementsfor split moulds may be used, depending on the desired shape and form ofthe building product.

In FIG. 5, the guiding channel comprises a longitudinally split mould,which consists of first longitudinal mould section 241 and secondlongitudinal mould section 242. First mould section 241 has a main wall270, an upper wall 271 and a lower wall 272. Upper wall 271 has acontrol joint ridge 273 which corresponds to a control joint groove inconcrete layer 275 of the building panel. Lower wall 272 has a similarcontrol ridge 274. Main wall 70 is supported and prevented from bowingoutwardly by steel beam 276. Second mould section 242 has a similar mainwall 277, upper wall 278, lower wall 279 and control joint ridges 280and 281, and is supported by steel beam 282. First mould section 241 hasa relief vent 200. Second mould section 242 also has a vent but is notshown as, in this embodiment, it is downstream of relief vent 200.

Upper walls 271 and 278 have abutting edges 283 and 284 respectively,and lower walls 272 and 279 have sealing lips 285 and 286 respectively.Sealing lips 285 and 286 are spaced apart sufficiently to providesliding seals with tongue 287 of expanded form 289. The spacing iseffected by clamps which are not shown.

Abutting edges 283 and 284 are held together by clamps, which are notshown. Upper walls 271 and 278 have longitudinal ridges 269 and 270respectively. Longitudinal ridges 269 and 270 form guides for keepingtongue 288 from freely floating within the split mould cavity. It willbe understood that tongue 288 may be positioned using means other thanridges 269 and 270. For example a single triangularly-shaped ridge onthe split mould may be used, and correspond with a triangularly-shapedlongitudinal notch in tongue 288.

Mould section 242 and beam 282 have a concrete inlet 290 (the extent ofwhich is delineated by walls 290 a) into which concrete may be fed.

In the embodiment shown in FIG. 5, expanded form 289 has fourlongitudinal external grooves 294 and 297.

In the process of making the building panel shown in FIG. 5, expandedform 289, which has tongues of the length required in the finishedbuilding panel, is pushed into the building channel so that tongue 287is slidingly guided between sealing lips 285 and 286 and tongue 288 isslidingly guided between longitudinal ridges 269 and 270.

Concrete 275 is first pumped into the cavity between mould section 241and expanded form 289. Concrete 268 is then pumped through aperture 290into the cavity between mould section 242 and expanded form 289. Excesspressure may be relieved through vent 200. Concrete 268 also moves intolongitudinal grooves 294 and 297.

Referring again to FIGS. 2 and 3, in operation expanded syntheticpolymeric form 55 is formed with polymer extrusion machine 49, usingsuitable extrusion dies to form the desired cross-sectional shape ofexpanded form 55. The expanded form 55 is then transported bycooperating continuous conveyors 50 so that expanded form 55 is fed intothe inlet of guiding channel 58. The expanded form 55 is fed betweensealing sleeves 59 and 54. One of the purposes of the sealing sleeves 59and 54 is to prevent escape of concrete upstream of the concrete inlets60 and 61. In the embodiments shown in FIGS. 2 and 3, concrete pumps 45and 46 are separated longitudinally along the guiding channel. In thisembodiment, concrete pump 45 first pumps concrete into the gap betweenbeam 41 and expanded form 55. The opposing side of expanded form 55 issupported by back plate 53 so that the thickness of concrete layer 52 iskept substantially constant. In order to attenuate any pressure surgesof the concrete as it enters the guiding channel, apertures 47 mayprovide some pressure relief. Concrete is then injected by concrete pump46 into guiding channel 58, so that a layer of concrete 51 forms on theopposing side of expanded core 55 to concrete layer 52. Vibrators orother mechanisms may be used to assist in packing the concrete.

The length of the guiding channel 58 is dependent on the speed of theprocess and the setting time for the concrete. As will be understood,different concrete mixtures will require different lengths of guidingchannel. It may be necessary, therefore to have several adjoinedsections of guiding channel 58. After leaving the guiding channel, thecontinuous building panel is supported and may be fed into a curingsection and/or a section with a cutter, in order to form building panelsof known length. The cut-to-length building panels are then loaded onpallets, ready for additional curing, further processing or shipping toa customer.

The expanded form 55 may be “solid” as shown in FIG. 1 but also may bemade with longitudinal cavities as shown in FIG. 4, or transversecavities. Such cavities allow for ease of installation of plumbing andwiring during installation at the building site. It will be understoodthat the transverse cavities are usually formed after making thebuilding panel in the above process, for example by coring out thecavities.

It will be understood that building products may also be made with anexpanded form which is not exposed along the longitudinal edges, i.e. isnot totally enveloped in facing material. In the case where onelongitudinal edge of a building panel is coated with concrete, the splitmould shown in FIG. 4 may be modified so that lips 85 and 86 abut oneanother to form a seal. In such a case, the form 89 would be guided byupper lips 83 and 84 and/or internal mandrels 101, 102 and 103.

It is further understood that although the above description refers onlyto concrete as the outer layers, other materials may be used, forexample plaster, as is described in reference to FIG. 6.

A corner moulding strip may comprise an expanded form 120 and a facingmaterial 121. As will be seen, expanded form 120 has two faces 122 and123 which are not coated with the facing material. Faces 122 and 124 arein sliding engagement with V-shaped first mould section 124 of atwo-part split mould. The outer surfaces of first mould section 124 aresupported by steel beams 125 and 126. Second mould section 127 is indirect contact with first mould section 124 at longitudinal edges 128and 129. Second mould section 127 is prevented from bowing outwards bysteel beams 130, 131 and 132. Second mould section 127 has an internalcross-sectional shape to conform to the desired external cross-sectionalshape of the finished moulding strip. Beam 131 and second mould section127 have an aperture 133, through which plaster may be pumped, from 134.In the case of the process illustrated with reference to FIG. 6, thereis only one pump and facing material inlet for introduction of facingmaterial 121. The process may also be operated to insert a glass fibreor similar scrim between facing material 121 and expanded form 120, orto embed the scrim in facing material 121. Facing material 121 may beconcrete, plaster of Paris, stucco or any other suitable material.

In the embodiment shown in FIG. 7, building panel 200 has an expandedform 204 with three longitudinal internal cavities 201, 202 and 203.Expanded form 204 also has external dovetail indentations 207. It willbe understood that the number and shape of any internal cavities andexternal dovetail indentations may be changed to suit the particularbuilding product. For example there may be a single internal cavity ormany internal cavities; they may be square, rectangular, circular or anyother shape in cross-section. Similarly, the number and shape of anyexternal dovetail indentations may be changed to suit the particularbuilding product. For example, the indentations may be triangular orrectangular in cross-sectional shape and they may be on one side of abuilding panel or both sides, depending upon the purpose to which thepanel is to be put.

The building panel shown in FIG. 7 is faced on one side with concretefacing 205 and on the other side with concrete facing 206. The concretefacings have complementary dovetail protrusions which are formed withindovetail indentations 207 so that there is a mechanical joint betweenthe facings and the expanded form. The expanded form 204 has opposingtongues 208 and 209 and concrete facings 205 and 206 have control jointridges 210 and 211 respectively, similar to those shown in theembodiment of FIG. 4.

The building panel of FIG. 7 also has ties 212 and 213, which aretransversely placed through expanded form 204. The ends of ties 212 and213 protrude from expanded form 204 into the facing materials 206 and207, to provide a mechanical means for strengthening the building panel200 and providing rigidity thereto. Ties 212 and 213 are preferablyplastic or metal. Suitable plastics and metals are known in the art.Although FIG. 7 shows the building panel having ties in addition to amechanical locking joint, it may not be necessary or desirable to haveboth.

It will be understood that building panel corner pieces and T-pieces canalso be made using the present process. Alternatively panels such as theone shown in FIG. 1 can be cut or adapted to form a corner or a T of abuilding or wall.

The split mould used in the present invention preferably has astationary mould section and a movable mould section. The movable mouldsection may be moved entirely away from the stationary mould section forcleaning and other purposes. Alternatively the movable mould section mayswing away from the stationary mould section, i.e. be pivoted at oneend.

What is claimed is:
 1. A continuous process, with upstream-anddownstream longitudinal directions, for making an elongated coatedbuilding product comprising a longitudinal expanded synthetic polymericform having a desired cross-sectional shape, and having a longitudinallycontinuous coating of a facing material on at least a portion of aperiphery of the cross-sectional shape, said process comprising: a)feeding the expanded-synthetic polymeric form longitudinally into theinlet of an elongated guiding channel which comprises a longitudinallysplit mould having an internal cross-sectional shape suitable to producea desired external cross-sectional shape of the coated building product;b) guiding the expanded synthetic polymeric form along the guidingchannel, without any means for pulling the expanded synthetic polymericform after the expanded synthetic polymeric form enters the inlet of theguiding channel; c) feeding the facing material into the split mouldthrough a first aperture in a first mould section of the split mould. 2.A process according to claim 1 wherein the split mould is a two-partsplit mould and the facing material is additionally fed through a secondaperture in a second mould section of the split mould, so that thefacing material is coated on at least two opposing sides of the expandedsynthetic polymeric form.
 3. A process according to claim 1 whereinfacing material is prevented from escaping upstream towards the inlet bysealing means between the split mould and the expanded syntheticpolymeric form.
 4. A process according to claim 1 wherein the coatedbuilding product is a moulding strip with at least one exposed face ofthe expanded synthetic polymeric form, in which process the exposed faceis in sliding contact with a second mould section of a two-part splitmould which has no apertures therein for introduction of facingmaterial.
 5. A process according to claim 4 wherein the facing materialis plaster.
 6. A process according to claim 1 wherein the buildingproduct is a building panel which is coated on at least two sides with afacing material selected from the group consisting of concrete andgypsum, in which process the expanded form is guided between first andsecond mould sections of a two-part split mould, facing material is fedthrough a first aperture in the first mould section and through a secondaperture in the second mould section.
 7. A process according to claim 2wherein the second aperture is downstream of said first aperture andthere are sealing strips between the expanded synthetic polymeric formand the first and second mould sections, at positions slightly upstreamof the first and second apertures.
 8. A process according to claim 1wherein there is a back pressure plate between the second mould sectionand the expanded synthetic polymeric form between the inlet of theguiding channel and the sealing strip which is upstream of the secondaperture.
 9. A process according to claim 2 wherein the polymericexpanded material is continuously provided from an extrusion or fusionmachine upstream of the inlet to the guiding channel.
 10. A processaccording to claim 1 wherein the expanded synthetic polymeric form ismade from expanded polystyrene, polyurethane, phenolic orpolyisocyanurate.
 11. A process according to claim 6 wherein theexpanded synthetic polymeric form is made from expanded polystyrene,polyurethane, phenolic or polyisocyanurate.
 12. A process according toclaim 1 wherein the facing material is selected from the groupconsisting of concrete, gypsum and plaster.
 13. An apparatus for acontinuous process, with longitudinal upstream and downstreamdirections, for making an elongated coated building product comprising alongitudinal expanded synthetic polymeric form, said apparatuscomprising: a) an elongated guiding channel which has a longitudinallysplit mould having an internal cross-sectional shape suitable to producea desired external cross-sectional shape of the coated building product,said guiding channel having an inlet and an outlet; b) means for guidingthe expanded synthetic polymeric form along the guiding channel, withoutany means for pulling the expanded synthetic polymeric form after theexpanded synthetic polymeric form enters the inlet of the guidingchannel; c) means for feeding facing material into the split mouldthrough a first aperture in a first mould section of the split mould;and d) sealing means in the guiding channel to prevent facing materialescaping upstream between the expanded synthetic polymeric form andmould sections, towards the inlet of the guiding channel.
 14. Anapparatus according to claim 13 wherein there is means for feedingfacing material into the split mould through a second aperture in asecond mould section of the split mould.
 15. An apparatus according toclaim 14 wherein the second aperture is downstream of said firstaperture and there is a sealing strip between the polymeric expandedmaterial and the second mould section at a position slightly upstream ofthe second aperture.
 16. An apparatus according to claim 13 wherein anextrusion or fusion machine for continuously making polymeric expandedmaterial is provided upstream of the inlet to the guiding channel, forfeeding polymeric expanded material into the inlet of the guidingchannel.